Automobile radio-cassette recorders and the like customarily have a radio portion and an insertion opening for recorded cassettes. The entire radio-cassette player unit is customarily introduced from the passenger compartment of the vehicle into an opening formed in the dashboard or front wall of the vehicle. The dashboard or front of the vehicle has a frame which, itself, may be separable therefrom, the frame and the housing of the radio-cassette player including interengaging snap-in connections to hold the radio or the frame portion of the vehicle.
"Vehicles", as referred to herein, does not only relate to automobiles, but to all kinds of vehicles capable of receiving persons, such as boats and the like.
Accessory radio-cassette players can be attached in the vehicle other than by interengaging snap-in connections, for example by screws or the like. The radio-cassette players, to which reference will be made hreinafter for simplicity, are preferably connected by such snap-in connections, however, since they premit ready removal for repair or exchange of different models upon insertion of appropriate tools available generally only to authorized installers or repair stations. Accessory apparatus as used herein refers to any electronic apparatus which includes a cassette tape player, that is, not only car radio-cassette players as such, but also video apparatus, computer apparatus, calling and telephone systems, automatic tape calling systems, citizen band (CB) radios, and the like.
Electronic theft locks or theft alarm systems often are so arranged that the accessory apparatus upon theft, that is, unauthorized removal, becomes useless. Yet, prior to breaking into a vehicle, a thief may not know this and the theft of the apparatus as such cannot, thereby, be prevented.